A shot peening processing method is used to provide a metal surface layer with compressive residual stress. In the shot peening processing method, media (shot media) is projected onto a work.
In a conventional shot peening processing method, after a combination of a shot peening processing apparatus and media is determined, a process condition is determined such that intensity and coverage required for a work can be achieved. An effective and systematic method for reducing a required time for shot peening process is required.
Japanese Patent Publication (JP-P2006-205342A) discloses a conventional method for setting shot peening condition. A relation between weight of shot media projected per unit time and an arc height value when coverage is 100% is obtained by using an air blast type shot-peening apparatus. When the weight of shot media projected per unit time is greater than a certain value, the arc height value is greatly reduced as the weight of shot media projected per unit time is increased. Based on the value, an optimum value of weight of shot media projected per unit time is set.